At 3:30 p.m. we reached a trail Roy Fero would later call a “cow patch”: a steep, roller coaster drop of dry mud the color of walnuts rising up just as high on the other side, maybe 60 feet, crest to bottom. Fero’s business partner Jeremy Purick sat shotgun in Rock Krawler’s signature Jeep Wrangler Unlimited; Fero followed in a modified Jeep Liberty. With the transmission in first and transfer case in 4wd low, the Unlimited tilted downward over the edge, and we lost the horizon to a spooky view of the plunging rough swath below.

“The idea with any type of rock crawling is to keep all four tires on the ground for as long as you can and go over the biggest object you possibly can,” said Fero earlier that day at Rock Krawler headquarters in Troy, New York. “That’s the key.”

Using a forklift, Fero had raised the front-left Goodyear tire on the Unlimited a yard off the ground in order to demonstrate the Jeep’s incredible Ramp Travel Index, a measure of the pliability of the suspension.

“If I can get this far up and not have any of the tires off the ground, I can go over rocks that other people can’t.” The Unlimited’s RTI shows it could tackle a rugby scrum without breaking a sweat.

Fero and Purick were engineers at Garden Way, a manufacturer of gardening equipment when they started conspiring on suspension modifications for their personal Jeeps. When Garden Way filed for Chapter 11 in 2001, the two transformed their hobby into Rock Krawler. It proved to be perfect timing.

Though lifted Jeeps have been around for decades, it was only when Jeep released the ’97 Wrangler—replacing the traditional leaf-spring suspension with the Quadra Coil system first seen on the Grand Cherokee—that aftermarket companies looked into developing long-arm suspensions.

“The market we’re in has only really grown up in the last three years,” Purick explained. “It’s a very young marketplace as far as that’s concerned. And rock crawling is a very young motorsport, for that matter.”

In its simplest terms, long-arm suspensions are replacement control arms that rotate the axle while maintaining a reasonable suspension geometry. Our ride for the day was equipped with Rock Krawler’s LJ 8.0-inch coilover X-Factor long-arm system. It replaces the Unlimited’s stock 16-inch control arms with a three-link front suspension and a four-link triangulated rear. The control arms are 40 inches long in the front and 36 inches in the back, meaning “the axle can articulate as much as it wants to off-road, but still maintain a very nice highway ride,” said Purick.

The system is Rock Krawler’s version of The Works. It comes with the long arms, coilover racing shocks with dual-rate springs and integrated bump stops, a skid plate made of quarter-inch laser-cut steel and everything else a Wrangler Unlimited needs to conquer Moab. That’s where the Jeep and off-road community go every Easter weekend. Needless to say, the narrow band of coagulated mud that we found ourselves on was an insult to the Rock Krawler Unlimited’s very Jeephood and its 4.56:1 gearing.

Descending the hill, vertigo gave way to the rhythm of progress. For every attack of the 37-inch Goodyears, there was a response, rebound or bounce—the kind of exercise that keeps your curiosity on edge. You grip the wheel straight and measure the gas. And then wait to see what happens; you anticipate which way the steering jerks. But the Unlimited moves forward no matter what, making even a rookie trail rider look good.

Only a water crossing, bridged by a tight formation of rocks, broke our momentum. Unsure of the Unlimited’s resilience, our first attempt was on the weak side. Slicked by water, the tires spun in a high pitch as the rpm rose. Directing tire placement from outside, Purick demanded more commitment. The gas pedal hit the floor. The wheels caught, paused, and pulled the Jeep straight. Though the steering wheel was cranked to the left toward a thick bush, the Detroit Lockers corrected the trajectory. The Jeep slammed through the foliage back onto the trail.

Somewhere in the distance, a big dog barked.

This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.io

This commenting section is created and maintained by a third party, and imported onto this page. You may be able to find more information on their web site.

A Part of Hearst Digital Media
Autoweek participates in various affiliate marketing programs, which means we may get paid commissions on editorially chosen products purchased through our links to retailer sites.